Kopacz has been sick with the coronavirus for over a week, but his health took a turn for the worse on Wednesday and he was re-admitted to hospital.
"Just a relentless high fever with uncontrollable coughing and everyday was the same, it wasn't getting better. It was either getting worse or just the same," said Kopacz.
He spoke with CBC News from his bed at London's University Hospital, where he's been for the past two days, taking long pauses between his sentences and sharp dry coughs that left him breathless.
"They did a series of scans and they saw how much stuff I had in my lungs and started recommending more puffers. No matter what they'd do, it didn't help," he said.
'It's not a joke'
"It sneaks up on you. You get hypoxic, you lose touch with reality, your will starts to break. It's an invisible assailant, it's just beating you no matter where you put your hands up — you can't block it."
Kopacz doesn't know how he became infected but his convalescence has given him time to reflect critically on those who don't take public health measures seriously.
"It's not a joke. When I see people with the mask half off their nose now, or even that conspiracy rhetoric, I don't know that I could even contain my rage right now," he said.
WATCH | Olympian on mask wearing and following the rules:
Alex Kopacz on his frustrations with 'the weakest link' and people not following COVID-19 rules. 0:44 "It hasn't been and it still isn't a joke and the reason it is constantly doing its loop is because we aren't actually doing our own due diligence."
From Kopacz's hospital bed, he's getting a first-hand glimpse of the dire situation facing Ontario hospitals in the third wave of the pandemic.
"I see a lot of really good nursing staff and doctors that are still in excellent spirits even if they are faking it," said Kopacz. "You can see how much people are suffering, I can see there's a challenge between offering resource availability and what can be offered right this second."
ICU fears
He says that he's already seeing the overflow of COVID-19 patients coming from places like Toronto.
There are now more than 800 COVID-19 patients in Ontario intensive Care Units (ICU) and the Olympian is hoping he won't be one of them.
"Of course it's a fear. I don't know if it's realistic or not. There's nothing to bank it on. It's another roll of the dice."
Kopacz wishes he had the opportunity to get the vaccine before he contracted the virus.
"If I had one, I probably wouldn't have been hit. I don't often get sick."
Kopacz was originally a shot putter who fluked into bobsleigh at 23 after a sprinting coach at London's Western University saw him run. He attended a talent camp and ended up training with the team.
The engineer soon started to medal in bobsleigh events, telling CBC he applied some of his mechanical know-how to the sport to maximize speed.
In 2018, Kopacz and pilot Justin Kripps tied for gold with the Germans in the two-man bobsleigh event in PyeongChang. They are the current reigning champions in the event.